This thesis investigates the constraints to collective behaviour and co-operative group formation in Cayo District, Belize. A special emphasis is placed on understanding the relationship between peasant farmers and the Belize Federation of Agriculture Co-operatives (BFAC). BFAC is a secondary level co-operative institution which has played a central role in the implementation of co-operativism in Cayo. Several problems currently faced by the federation prove to reflect the constraints to collective behaviour and co-operative group formation.Beginning with an introduction to co-operativism and BFAC, the thesis later moves to a review of several problems affecting the federations sustainability. Ego-focused opportunism becomes a key issue and forces the analysis to explain farmers actions in terms of individual responses to change. A central contention is that a continued influx of capital and resources from donor agencies exacerbates local individualistic strategies, leading to an increase in the occurences of opportunism. By the same token, the same agencies could provide a cohesive forces strong enough to bind individuals.